Granted Patent
Utility
US 4,861,856 · App. 07/240,642
Process for the preparation of polyketone and poly(ketone-sulfone) polymers
Inventors:
W. Ronald Darnell, Winston J. Jackson, Jr.
Patented Case
View Patent ↗
Granted: Aug 29, 1989
Filed: Sep 6, 1988
Inventors
W. Ronald Darnell
Winston J. Jackson, Jr.
Assignee (at issue)
EASTMAN KODAK COMPANY
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.